Flash: Controlling Sound

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Flash Controlling Sound

• Presentation by Mindy McAdams

2
ActionScript (so far)

• From Lessons 1 through 7
• stop()
• play()
• gotoAndStop("someframelabel")
• gotoAndPlay("otherframelabel")
• The script can be written on a button or on a
  frame

3
ActionScript for buttons

• If script is on a button
• on (release) stuff here
• Alternatively -- if a button has an instance
  name, you can put the script on the Timeline this
  way
• rewind_btn.onRelease function () stuff here
  

on (release) stuff here
rewind_btn.onRelease function () stuff here

4
ActionScript movie clips

• If you need to make a movie clip stop playing (if
  the instance name is clouds_mc) from the main
  Timeline
• Or if the movie clip needs to tell the main
  Timeline to stop playing

clouds_mc.stop()
_parent.stop()
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New, exciting ActionScript

• What is a variable?
• A kind of container for data
• Each variable has a name (static)
• Each variable has a value (dynamic)
• Examples of variables (name, left and value,
  right)
• n 27
• myColor "orange"

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ActionScript 2.0 variables

• Not in the book
• AS 2.0 would like script to be more formal in
  style
• Examples of the initial declaration of variables
  in AS 2.0
• var n 27
• var myColor "orange"

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ActionScript 2.0 variables

• In fact, AS 2.0 would like things to be EVEN MORE
  formal
• Examples of the initial declaration of variables
  in AS 2.0, including strict data typing
• var nNumber 27
• var myColorString "orange"

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Selecting ActionScript version

• To make life easy, when following the book, you
  can simply change the Publish Settings to AS 1.0
• But eventually, people will use AS 2.0 for
  everything

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ActionScript variables

• We should formally declare our variables
• var n 27
• var myColor "orange"
• You can do that in AS 1.0 or 2.0
• However we need not use strict data typing
  (Number, String, etc.)

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ActionScript variables

• How does a variable work?
• var n 27
• n n 1
• if (n 28) stuff here
• Another example
• var myColor "orange"
• if (myColor ! " blue")
• stuff here

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ActionScript operators

• is equivalent to
• ! is NOT equivalent to
• gt is greater than
• lt is less than
• gt is greater than or equal to
• lt is less than or equal to

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Variables in Lesson 8 (Sound)

• The book says
• x new Sound()
• Here the variable is x and we are declaring it
  for the first time
• So to be more formal and correct
• var x new Sound()
• Only the first time you use x in a movie do not
  write var after the first appearance of the
  variable

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Variables in Lesson 8 (Sound)

• A variable name can be any word (except the
  reserved words see pp. 479 - 480)
• Its common to use letters such as x, y, and z
  as names of variables
• Its also common to use camel case in the name
  -- e.g. mySound, theMusic, etc.

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Variables in Lesson 8

• After we have declared a variable (with var), we
  can use it to do things -- rather like an
  instance name
• x.start(0, 0)
• x.stop()
• These are the basics of audio in Flash
• (Well get back to this shortly)

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Bringing sound into the FLA

• The only script difference between the two
  methods for the Sound object concerns how you
  associate your audio file with your variable
• x.attachSound("crossroads")
• or
• x.loadSound("rainforest.mp3", true)

x.attachSound("crossroads")
x.loadSound("rainforest.mp3", true)
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External MP3 files (loadSound)

• To load an external audio file, the file MUST BE
  in the MP3 file format
• Also, the file must have a sampling rate of one
  of these three values (on pp. 216 217)
• 11.025 kHz (doesnt sound great)
• 22.05 kHz (usually best choice)
• 44.1 kHz (CD quality big file size)
• Otherwise, you will have distorted sound

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Starting and stopping sound

• To stop a Sound object represented by the
  variable name x
• x.stop()
• (Exactly like stopping a movie clip)
• To play a Sound object (from the beginning)
• x.start(0, 0)
• Script can be on a button or on a frame

x.stop()
x.start(0, 0)
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Options for starting sound

• This will start the sound from the beginning AND
  play it only once
• -
• This will start the sound from the beginning and
  loop it 100 times
• -
• This will start the sound 20 seconds after the
  beginning and play it only once
• -

x.start(0, 0)
x.start(0, 100)
x.start(20, 0)
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Pausing sound

• Before you pause an audio file, you must
  determine how much has already played
• Then you will be able to start it (later) from
  the same point
• This property is called position

var p p Math.floor(x.position/1000)
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Pausing sound (2)

• Say the sound file had already played for 5.2
  seconds (5,200 milliseconds)
• This script will get the number 5,200 and divide
  it by 1,000
• Then it will round down the result to a whole
  number (not a decimal)
• Result p 5

p Math.floor(x.position/1000)
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Pausing sound (3)

• If you have the value of p, you can use that
  value to restart the audio file at the correct
  point after it has been paused
• P
• x
• If the value of p were 5, then the audio would
  immediately start playing from the point 5
  seconds into the file

p Math.floor(x.position/1000) x.start(p, 0)
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Adjusting the volume

• If all you need to do is mute the audio (while it
  continues to play)
• -
• If you then need to return the audio to the
  maximum volume
• -
• The volume range is exactly 0 to 100

x.setVolume(0)
x.setVolume(100)
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ActionScript basics

• From Lessons 1 through 7
• stop()
• play()
• gotoAndStop("someframelabel")
• gotoAndPlay("otherframelabel")
• You will use these in almost every Flash movie

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ActionScript for audio (basics)

• From Lesson 8 (x can be any name)
• var x new Sound()
• x.attachSound()
• x.loadSound()
• x.start(0, 0)
• x.stop()
• You will use these to control sound in any Flash
  movie that requires it

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ActionScript/audio (advanced)

• From Lesson 8 (x can be any name)
• var x new Sound()
• var p 0
• p Math.floor(x.position/1000)
• x.start(p, 0)
• x.setVolume(0)
• x.setVolume(100)
• You will use these to control sound in
  conjunction with buttons in the Flash movie

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Flash Controlling Sound

• The End
• Presentation by Mindy McAdams
• gt Flash Journalism Lesson 8